1. Field of the Invention
The present invention relates in general to a weft picking device of an air jet type weaving loom, and more particularly to a weft picking device of the type which comprises a row of air guide members, a main nozzle, and auxiliary nozzles associated with some of the air guide members to assist the weft picking operation.
2. Description of the Prior Art
In an air jet type weaving loom, there is known a so-called "sub-nozzle type weft picking device" which comprises generally a row of closed type air guide members by which the weft carrying air guide channel is defined, a main nozzle from which compressed air is ejected to eject the weft yarn into the air guide channel, and auxiliary nozzles associated with some of the air guide members to eject auxiliary air into the air guide channel to assist the weft picking operation. The aligned air guide members form an axially extending slot through which the picked weft yarn in the air guide channel passes out upon beating operation of the loom. For providing the air guide channel and the slot, each air guide member has therein an air guide opening which forms a part of the air guide channel, and a slit which is connected to the air guide opening and forms a part of the axially extending slot.
As is known, the sub-nozzle type weft picking device as mentioned above has exhibited excellent weft picking function as compared with a single nozzle type weft picking device which is not provided with the auxiliary nozzles corresponding to the auxiliary nozzles of the sub-nozzle type weft picking. device. However, as will become apparent as the description proceeds, even in such sub-nozzle type weft picking device, it is difficult to continuously carry out perfect weft picking because of inherency of employing the auxiliary nozzles.